Sexual dysfunction after prostate surgery is more common than previously reported, says Hutchinson Center study

Media briefing: A media briefing will be held at 1 p.m. PST Tuesday, Jan. 18 at the Center's Metropolitan Park East Campus, 1730 Minor Ave., between Olive and Howell streets. A Media Relations representative will greet you in the lobby and escort you to the briefing room. Free parking is available in an underground garage; entrance off Minor Ave. A map of the site is available upon request.

SEATTLE -- Sexual dysfunction among men who undergo prostatectomy (prostate-removal surgery for prostate cancer) appears more prevalent than previously reported, according to a multi-center study led by an investigator from the Fred Hutchinson Cancer Research Center in Seattle.

The results will appear in the Jan. 19 issue of the Journal of the American Medical Association.

Funded by the National Cancer Institute, the Prostate Cancer Outcomes Study is the first comprehensive, population-based assessment of sexual function and urinary continence among men treated with radical prostatectomy for early stage, localized prostate cancer. It is also the first study to examine the sexual and urinary side effects of such surgery in minority populations.

The study followed 1,291 men between the ages of 39 and 79 in six states. Sexual and urinary function was assessed, via self-administered questionnaire, at six months, a year and two years after diagnosis (all of the men had surgery within six months of diagnosis).

At 18 or more months after surgery, the impotence rate among these men was nearly 60 percent. Previous outcome studies, in contrast, have assessed impotence rates a year or more after surgery ranging from as low as 29 percent to as high as 75 percent.

Differences in patient mix, study size and data-collection methods may explain the wide range of study results, says principal investigator Janet L. Stanford, Ph.D., head of the Hutchinson Center's Prostate Cancer Research Program and a member of its Public Health Sciences Division.

"Previous impotence estimates have been based on selected case series from a few institutions that do a substantial number of these procedures," she says, referring to studies based on outcomes data from a handful of well-known prostate-surgery centers.

"Men who undergo radical prostatectomy at such places are a select group who tend to be healthier, younger and may be more likely to bounce back and have a different outcome than patients in the general population," says Stanford, also a research professor of epidemiology at the University of Washington School of Public Health and Community Medicine.

Participants in the PCOS study represent a large, community-based group of Caucasian, African-American and Hispanic men living in Connecticut, New Mexico, Utah, metropolitan Atlanta, Los Angeles County and King County, Wash., which includes Seattle. (The participants were gleaned from population-based cancer registries of the National Cancer Institute's Surveillance, Epidemiology and End Results, or SEER, program.)

"Because we studied men from various communities throughout the country who were treated at a variety of institutions, our findings are likely to be more representative of the urinary and sexual function following surgery for localized prostate cancer than those from some earlier studies, which drew on patients from individual or single institutional clinical practices," Stanford says.

The majority of participants were middle-income, married, Caucasian retirees with a high-school or college education.

In addition to its population-based design, another strength of the study was that it relied on self-reporting, not second-hand information. "We asked the patients about their experiences directly. We didn't abstract the information from medical records or expect their surgeons to tell us how successful the procedure was in terms of avoiding side effects," Stanford says. The participants-- medical records were accessed only to confirm details regarding the diagnosis, treatment and clinical characteristics of their disease.

Impotence rates varied according to the type of radical prostatectomy attempted: "nerve-sparing" vs. "non-nerve sparing," referring to whether the nerve bundles on each side of the prostate that control sexual function had been preserved. The ability to spare one or both of these nerve bundles depends not only upon the surgeon's training and experience, but also on the extent and location of the cancer.

A year and a half after surgery, impotence rates ranged from 66 percent among those who underwent non-nerve sparing prostatectomy to 56 percent among those in whom a bilateral (two-sided) nerve-sparing procedure was attempted.

Prior to the diagnosis of prostate cancer, nearly 18 percent of the patients felt that sexual function was a "moderate to big problem." Two years after diagnosis, that number jumped to 42 percent. However, men who reported better sexual function before surgery also tended to report a higher level of satisfaction with sexual performance afterward.

Age and education also had an impact on the frequency of impotence.

Men in the youngest age group (those under age 60) reported more frequent sexual activity and regained sexual function sooner compared to the older men. Men with a college or post-graduate education reported the highest frequency of sexual activity and the lowest level of concern about sexual performance post-surgery compared to those with less education.

Sexual function also varied by race, with African Americans experiencing a better outcome; 38 percent of blacks reported erections firm enough for sexual intercourse at 24 months compared to only 21 percent of whites and 26 percent of Hispanics. "This is the first study to evaluate post-prostatectomy sexual function in minority populations, so more research is needed to confirm these findings," Stanford says.

The study also looked at the effect of the surgery on urinary control. Two years after diagnosis (at least 18 months after surgery), nearly 9 percent of the participants reported that incontinence remained a "moderate to big problem," with about 40 percent reporting occasional urinary leaking, 7 percent complaining of frequent leaking and 2 percent having no urinary control. Previous studies have documented long-term incontinence rates after radical prostatectomy ranging from 4 percent to 40 percent.

While the length of time after surgery was the strongest predictor of urinary function, other factors influenced incontinence rates as well. For example, men of higher income reported better function than those of lower income. Marital status also seemed to have a significant influence; 33 percent of married men reported no incontinence at two years after diagnosis, compared to 26 percent of unmarried men.

Age also was significantly related to the degree and frequency of incontinence. Compared to younger men, those in their mid to late 70's experienced the highest level of incontinence; 14 percent reported total incontinence two years after diagnosis, compared to rates ranging from less than 1 percent to 4 percent among men under age 60. In addition, younger men regained function sooner than older men.

Despite the risk of side effects, about 75 percent of those surveyed were "delighted or pleased" with their surgery, and only 4 percent were dissatisfied. A year and a half after surgery, 72 percent of the men said they would make the same treatment choice, although this varied by race (56 percent of blacks said they would choose the surgery again, as compared to 76 percent of whites and 61 percent of Hispanics). Only 7 percent of the men reported that they would not choose radical prostatectomy again.

"To make informed choices about treatment alternatives, prostate-cancer patients and their doctors need accurate information to assess the potential and pattern of complications associated with each option," Stanford states in JAMA.

"I think it's important for men in the general population to be offered the most accurate reflection possible of the risks associated with prostatectomy, rather than to simply be quoted the best statistics available," she says. "They need to make the most informed decision possible when deciding on prostate-cancer treatment."

This multi-center study also involved researchers from Norris Comprehensive Cancer Center at the University of Southern California, Los Angeles; the New Mexico Tumor Registry and the University of New Mexico Health Sciences Center, Albuquerque; the Utah Cancer Registry and the University of Utah School of Medicine, Salt Lake City; the Georgia Center for Cancer Statistics, Rollins School of Public Health, Emory University, Atlanta; the University of Connecticut Health Sciences Center, Farmington; and the National Cancer Institute, Division of Cancer Control and Prevention, Bethesda, Md.

Editor's note: For more information, to arrange an interview with Dr. Stanford, or to obtain a copy of the JAMA paper, please call Kristen Woodward at (206) 667-5095.

# # #

The Fred Hutchinson Cancer Research Center is an independent, nonprofit research institution dedicated to the development and advancement of biomedical technology to eliminate cancer and other potentially fatal diseases. Recognized internationally for its pioneering work in bone-marrow transplantation, the Center's four scientific divisions collaborate to form a unique environment for conducting basic and applied science. The Hutchinson Center is the only National Cancer Institute-designated comprehensive cancer center in the Pacific Northwest. For more information, visit the Center's Web site at <www.fhcrc.org>.

TREATMENT ALTERNATIVES FOR EARLY STAGE,

LOCALIZED PROSTATE CANCER

Prostate cancer is the most frequently diagnosed solid tumor in American men. An estimated 179,300 men will be diagnosed this year, and more than 70 percent of these patients will have early stage, localized disease.

Treatment options for men with tumors confined to the prostate and who have at least a 10-year life expectancy include radical prostatectomy, external-beam radiation, brachytherapy and expectant management, also known as "watchful waiting."

Each of these approaches is associated with a different spectrum of side effects that may impact quality of life in the short or long run.

Radical prostatectomy -- the surgical removal of the prostate and some of the tissue around it. Radical prostatectomy is done only if the cancer does not appear to have spread outside the prostate. There are two types of prostatectomy:

perineal prostatectomy -- when the prostate is removed through an incision between the scrotum and anus (the perineum); and

retropubic prostatectomy -- when the prostate is removed through an incision in the lower abdomen.

A more refined approach to prostate-removal surgery, available at select centers since the early ‘80s, is called "nerve-sparing" or "anatomical" radical prostatectomy, which involves using long, thin surgical instruments to cut free and protect the nerves and valves surrounding the prostate that control sexual function. Whether one or both nerve bundles can be spared during surgery depends on the extent and location of the cancer. The outcome and side effects also depend largely on the experience and training of the surgeon.

External-beam radiation therapy -- using high-dose X-rays, delivered from a machine outside the body, to kill the cancer cells. Treatment is delivered daily in 15- to 30-minute sessions for approximately seven weeks.

Brachytherapy -- also known as radioactive-seed implantation, this treatment delivers radiation via many small radioactive "seeds" that have been implanted into the prostate. The seeds, which are no larger than grains of rice, are inserted a short distance from the tumor. Some types of seeds remain permanently in place, while others are later removed.

Expectant management -- this alternative to medical and surgical treatment is also known as "watchful waiting." This means opting to monitor the cancer through regular PSA testing, digital-rectal exams and/or transrectal ultrasounds instead of pursuing immediate treatment. As soon as any changes are detected that indicate the cancer is progressing or growing, active treatment can then be pursued.